Dividends (Details) - USD ($)	Nov. 10, 2015	Aug. 25, 2015	May. 20, 2015	Feb. 23, 2015	Nov. 11, 2014	Aug. 19, 2014	May. 28, 2014	Feb. 24, 2014
Dividends, Common Stock [Abstract]
Dividend per share (usd per share)	$ 0.54	$ 0.54	$ 0.54	$ 0.54	$ 0.54	$ 0.54	$ 0.54	$ 0.54
Total amount declared	$ 293,000,000	$ 300,000,000	$ 303,000,000	$ 303,000,000	$ 307,000,000	$ 308,000,000	$ 307,000,000	$ 309,000,000

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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Balance Type:	debit
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